Useful in air purification, a high-efficiency filter is capable of effectively collecting almost all harmful microorganisms. However, microorganisms collected by the filter may live for a long period of time, and may even proliferate. To solve such problems, a variety of antimicrobial filters have been developed.
As such, antimicrobial techniques for coating the surface of a filter with an antimicrobial material have been employed, especially antimicrobial techniques for a filter for air purification wherein ion clusters are generated at the front of the filter and ions are thus attached to microorganisms collected by the filter to thereby kill the microorganisms. However, dust may function as a protection barrier for microorganisms due to continuous accumulation thereof on the filter, making it impossible to effectively kill the harmful microorganisms by the conventional techniques.
Also, as illustrated in FIG. 1, attempts have been made to irradiate a UV light source 3 onto the surface of a filter 1 so as to kill microorganisms 2, but the UV light 3 is irradiated only onto the surface of the filter 1 and cannot kill the collected microorganisms 2 in the filter 1.